1. Field of the Invention
The present invention relates to an intra-vascular device and method. More particularly, the present invention relates to a device used to treat aneurysms where a branch connection from a main stent graft crosses the ostium of a branch vessel.
2. Description of Related Art
A conventional main stent graft typically includes a radially expandable reinforcement structure, formed from a plurality of annular stent rings, and a cylindrically shaped layer of graft material defining a lumen to which the stent rings are coupled. Main stent grafts are well known for use in tubular shaped human vascular or other body vessel.
Endovascular aneurysmal exclusion is a method of using a main stent graft to partially or completely isolate an aneurysmal sac from systemic blood pressure by preventing pressurized blood flow from pressurizing the interior of an aneurysm, thereby reducing the risk of rupture of the aneurysm and the need for an invasive surgical intervention.
Illustratively, the main (body) stent graft was placed in the main vessel, e.g., the aorta, to exclude an aneurysm. A (branch) fenestration (opening) in the side of the main body provides an opening for blood flow to a branch vessel which would otherwise be obstructed by the position of the main body across the ostium of the branch vessel. A branch graft or branch stent graft was then inserted through the side opening and into the branch vessel spanning any gap between the outside of the branch opening in the main body and the ostium of the branch vessel, and carrying blood across the gap without pressuring the aneurysm.
Initially, the main stent graft was deployed in the main vessel such that an opening in the sidewall of the main stent graft was aligned with the branch vessel. A branch graft having a silicone flange was then passed through the opening in the main stent graft and deployed in the branch vessel. The silicone flange was configured to engage with and seal with the opening in the sidewall of the main stent graft. However, the silicone flange had a relatively large delivery profile and was somewhat inflexible thus limiting the range of applications in which the silicone flange with attached branch grafts could be used.